After schema update , Replication is breaking without raising error

I am modifying the table schema at publisher by adding addtional columns on publisher table and the schema is replicated over to subscriver without any problems. But when I am inserting values into these new fields by using the below query:UPDATE dbo.eventSET block_ = 1, fuel = f_usedValues are not getting replicated over to subscriber. But the replication monitor does not report any problem even though after this update, replication is not functioning (i.e.) any modification not getting transmitted over to subscriber and breaks is in inconsistent state.

As our publications size is huge , we cannot generate snapshot agent. So to avoid this , we configured our subscriptions to use "REPLICATION SUPPORT ONLY" option.
My guess is , as we are not updating the table by referencing Primary key column, so the replication does not know, what to update.Thoughts ?UPDATE dbo.eventSET block_ = 1, fuel = f_used
Thanks.